In the electronic industry, many times, it is necessary to prevent solder from flowing into printed circuit board holes and onto male and female connectors mounted on printed circuit boards. Most printed board assemblies are wave soldered, which consists of exposing the entire underside of a printed circuit board to a molten wave of solder. Prior techniques of restricting solder flow have been to use toothpicks inserted into printed circuit board holes and non-solderable caps hand inserted over connector terminals. The hand inserting operations are costly and the additional handling of the printed circuit board can adversely affect its subsequent solderability.
One method of forming a conductive through connection in a printed circuit board is to use a metal "eyelet", a preformed metallic component, that is inserted into a printed circuit board. Eyelets are also used to insure good solderability of components to printed circuit boards. Individual eyelets are formed separately or in strip form on a roll. The formed eyelets are then loaded into a standard eyeleting machine which inserts them into a printed circuit board. Thus the material cost of the individual preformed eyelets and the cost of inserting the eyelets into a printed circuit board are both incurred during printed circuit board assembly.